The intent of this pilot study is to adapt human PET procedures for use with the smaller macaque monkey brain. PET studies will provide information about changes in glucose metabolism in different brain regions as a result of various experimental interventions. This will provide investigators with a noninvasive tool to examine neural functioning in vivo. Examples of current research being conducted by Primate Center affiliates that could benefit from PET technology include studies of the effects of HIV infection, the examination of brain and behavior after experimentally induced seizures, the investigation of effects of teratogen exposure on brain development, and work focusing on different aspects of visual processing. PET will augment the use of macaques in basic research, contribute to models of human clinical conditions, and potentially provide a useful clinical measure for animals manifesting symptoms of brain dysfunction. It is anticipated that procedures deve lope d during the course of this pilot study will be a widely used resource that will be available to research affiliates of both the Primate Center and the Center on Human Development and Disability. To date, we have completed our planning part of this study and are rehearsing the procedures. We expect to test the first subject in April 1999. FUNDING NIH grants RR00166 and MH01201.